Although a burgeoning body of literature has revealed substantial racial and ethnic differences in exposure to environmental hazards, we have very little information about the micro-level processes that shape and reinforce this environmental inequality. Certainly, there is evidence of racial biases in the process through which industrial facilities are sited. However, in the context of high residential mobility, the persistent concentration of minorities in hazardous neighborhoods necessarily reflects racially differentiated patterns of mobility between neighborhoods with varying levels of pollution. Indeed, the most common theoretical explanations for environmental inequality implicate household-level residential mobility patterns as the key mechanism through which environmental inequality is maintained. To date, however, data limitations have prevented the appropriate examination of household-level mobility patterns between neighborhoods with varying hazard levels, much less possible racial and ethnic differences therein. This dearth of information on household-level mobility processes not only leaves untested key theoretical arguments about the causes of environmental racial inequality, it also leaves open a number of questions related to the source of substantial variation in the magnitude of this inequality. This proposed study seeks to address these significant gaps in the literature by merging individual-level residential mobility data from the nationally representative Panel Study of Income Dynamics (PSID) with neighborhood-level demographic data from the U.S. Census and environmental hazard data derived from the Environmental Protection Agency's (EPA) Toxics Release Inventory (TRI), Biennial Reporting System (BRS);Resource Conservation and Recovery Act Information System (RCRIS);and Risk-Screening Environmental Indicators (RSEI) project. The study will utilize a new and innovative Geographic Information Systems (GIS) technique that weights the potential impact of each hazard inversely according to geographic distance, allowing us to measure hazard proximity more precisely than has been possible in prior research, and the hazard data provide information on multiple types of environmental hazards, allowing us to compare the relative impact of different environmental hazards on residential mobility. In addition, the study will draw on the theoretical insights of neighborhood attainment research to provide a more nuanced theoretical understanding of the role residential mobility plays in the creation of environmental racial inequality. Combining these theoretical insights with more appropriate multi-level data makes it possible to address, for the first time, a number of research question that are crucial for understanding the processes that affect environmental inequality. PUBLIC HEALTH RELEVANCE: Recent research has found that residential proximity and exposure to environmental hazards can have a deleterious effect on physical and psychological health and perceptions of social disorder, and that perceptions of social disorder can negatively affect psychological health. Thus, in examining whether there are racial and ethnic differences in household-level mobility patterns between neighborhoods with varying levels of environmental hazard, this study will shed light on the public health implications of racially stratified mobility processes. It will also inform research on racial and ethnic health disparities in the United States.